PI3K pathway is the most common place where human cancer cells mutate which may lead to cell proliferation, activation and signal amplification.
PI3K kinases (phosphatidylinositol 3-kinases, PI3Ks) belong to the lipid kinase family and are capable of phosphorylating the 3′-OH end of the inositol ring of phosphatidylinositols. Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase composed of a regulatory subunit p85 or p101 and a catalytic subunit p110. It catalyzes the phosphorylation of phosphatidylinositol 4,5-bisphosphate (PIP2) to form phosphatidylinositol 3,4,5-trisphosphate (PIP3), thereby activating downstream Akt, etc., so as to play a key role in proliferation, survival, metabolism and the like of cells. Therefore, the inhibition of phosphatidylinositol 3-kinases can influence the PI3K pathway, thereby inhibiting the proliferation and activation of cancer cells.
The tumor suppressor gene PTEN (phosphatase and tension homolog deleted on chromosome ten) dephosphorylates PIP3 to generate PIP2, thereby achieving the negative regulation of PI3K/Akt signal pathway, inhibiting cell proliferation and promoting cell apoptosis. The frequent occurrences of PI3K gene mutation and amplification in cancers, the absence of PTEN in cancers and the like indicate that PI3K is closely associated with the occurrence of tumors.